Muggle Tom Riddle abandoned his wife, a descendant of
Salazar Slytherin, and unborn child when he learned she was a witch (CS17).

1927

Born in Little Hangleton (GF1, 33). Voldemort's mother lives just
long enough to name him. Tom Marvolo Riddle is raised in a Muggle
orphanage (CS13).

1938

Begins his first year at Hogwarts School and is sorted into Slytherin. He
hears of the Chamber of Secrets and begins to learn all he can about it.
He must return to the Muggle orphanage during school breaks. Outwardly
he is a model student, but he secretly studies Dark Arts.

Date unknown, but during his time at Hogwarts

Tom creates a new name for himself, rearranging the letters of his
name to spell, "I AM LORD VOLDEMORT". He uses the name
among his most intimate friends at Hogwarts and wanted it, one day,
to be a name wizards will fear to speak (CS17).

1942

September - Begins fifth year at Hogwarts.

1943

Tom opens the Chamber of Secrets and releases the basilisk into
the school. Several students are injured and one (Myrtle) is killed.

June 13 - He stages the capture of Hagrid and Aragog, making it seem
they were responsible for the attacks. He receives a trophy for
Special Services to the school. Tom records the "memory"
of himself in a diary to lead another to finish the work of ridding
the school of "those unworthy to study magic".

1944

Summer. Tom murders his grandparents and father in their home in
Little Hangleton (GF1).

September. Begins his seventh year at Hogwarts. Tom is Prefect,
Head Boy, and receives a Medal for Magical Merit.

1945

June. Leaves Hogwarts and disappears.

1945 - 1970

Tom travels widely and sinks even more deeply into the dark arts in
his quest for immortality and power. He undergoes many dangerous
magical transformations and consorts with those considered the
"worst" of the wizarding world (CS18).

c. 1970

Tom Riddle returns, now openly calling himself Lord Voldemort.
He is so changed that few recognize him as Tom Marvolo Riddle (CS18).

1970s

Lord Voldemort begins to gather followers and gain power. The
Death Eaters use the Unforgivable Curses and the years of his
ascent to power are marked by disappearances, deaths, torture,
terror and atrocities in both the wizarding and Muggle
worlds. The Death Eaters wear the Dark Mark and send that sign
into the air where they have killed.

1979 - Voldemort gains a spy in Peter Pettigrew, who has
turned traitor in the ranks of the
Order of the Phoenix.

1980

Sometime in this year (or late in 1979) Voldemort is informed
of Sibyll Trelawney's first prediction: that a boy with the
potential to vanquish him would be born at the end of July.

1981

Voldemort targets the Potters, but they learn of this
from a spy in Voldemort's following and go into hiding.

October 31. Pettigrew, having been made their Secret Keeper,
betrays the Potters. On Pettigrew's information, Voldemort goes to
their home; he kills James, then Lily when she tries to protect
her son. When he attempts to kill Harry, the spell rebounds
and he is "ripped" from his body. He flees far from
human society and the Aurors to wait for his Death Eaters to
find and restore him.

1981 - 1991

The disembodied Voldemort lurks deep in an Albanian forest,
concealing himself from the Aurors still searching for him.
The need to hide severely hampers Voldemort's efforts to gain
the use of an effective body.

1991

Professor Quirrell meets Voldemort in the forest and
is bent to his will.

July 31. Influences Quirrell to try to steal the Sorcerer's Stone
from a vault in Gringott's.

October 31. Voldemort and Quirrell send a Mountain Troll into
Hogwarts to create a diversion while they try, unsuccessfully,
to take the Stone.

1992

June. Voldemort and Quirrell win past most of the enchantments
protecting the Stone, but are foiled at the Mirror of Erised.
Harry Potter nearly loses his life in holding Quirrell/Voldemort
off the Stone. When Albus Dumbledore arrives, Voldemort
flees back to the forest in Albania, leaving Quirrell to die.

September. The "memory" of Tom Marvolo Riddle is able to
use Ginny to open the Chamber of Secrets.

October 31. Mrs. Norris, Filch's cat, is the first victim petrified
by the basilisk. Several more students are injured in the following
months. Tom learns of Harry Potter and his encounter with
Lord Voldemort and wants to discover how Harry survived the curse
that should have killed him and instead nearly destroyed
Voldemort (CS).

June. Tom lures Harry to the Chamber and challenges him but is
defeated when Harry destroys both the basilisk and the diary (CS17).

1994

Summer, after 6 June. Peter Pettigrew (Scabbers/Wormtail), having been
forced out of hiding, finds Voldemort in Albania. Wormtail captures
Bertha Jorkins and from her, using a powerful memory charm,
Voldemort gains information to form a new plan to return to his body with
the assistance of Wormtail and Bartemius Crouch Jr. Voldemort kills Bertha
Jorkins (GF).

August. Voldemort, Wormtail, and Nagini use the old "Riddle House"
in Little Hangleton where they encounter and kill Frank Bryce (GF1).

June 24.
Harry and Cedric Diggory, touching the Triwizard Cup together, are both
brought to the churchyard at Little Hangleton, where Wormtail kills
Cedric with Voldemort's wand, then finishes helping Voldemort to invoke
an "old piece of Dark Magic". Restored to his body, Voldemort
summons the Death Eaters to him and begins reestablishing his dominance
over them. As part of this, Voldemort challenges Harry to a Wizard Duel.
His plans are thwarted when their wands, being "brothers",
won't work properly against each other. The "shadows" of those
Voldemort most recently killed are forced from his wand; they support
Harry and assist his escape.

Between June 24 and 31 August. Voldemort becomes obsessed with hearing
the full details and exact wording of Sibyll Trelawney's first prophecy.
He particularly wants to know how to destroy Harry Potter
(OP1-10 dreams, OP37).

sometime in July (a month or so after his return) Voldemort's
envoys to the giants are encountered by Hagrid and Madame Maxime (OP20).

December. Voldemort takes possession of a giant snake, and attempts
to gain entry to the Department of Mysteries in the snake's body. He
is thwarted by Arthur Weasley (OP21).

1996

January. The mass breakout of the Death Eaters immured in Azkaban
Fortress makes Voldemort the happiest he's been in 14 years (OP24).

March. Voldemort learns from Rookwood that only those to whom
a prophecy refers can remove the record of that prophecy from
its resting place in the Department of Mysteries. He subjects
Avery to the Cruciatus Curse for previously giving him bad
information on the subject (OP26).

June. Voldemort feeds Harry a false vision of Sirius being tortured,
and succeeds in luring Harry into the Hall of Prophecy in the Department
of Mysteries. Harry retrieves the prophecy sphere, but it is smashed
in the ensuing battle between the Death Eaters on one side and the
D.A. (reinforced by the Order of the Phoenix) on the other. Voldemort
then enters the Ministry of Magic in person and duels with Dumbledore.
At the conclusion of the duel, Voldemort takes possession of Harry in
an attempt to convince Dumbledore to kill Harry on the chance of
destroying Voldemort (OP31 - 36).